Unisia Jecs Corporation

Nissan Motor Company Limited

Akira Hidaka

Seinosuke Hara

Yoshihiko Yamada

Shinichi Takemura

Makoto Nakamura

Shoji Morita

Tsuneyasu Nohara

Hirokazu Uehara

Noriomi Hosaka

Nobutaka Hayashi

Yukio Yamakawa

A valve-operating device for an internal combustion engine equipped with two cylinder banks each having a variable valve timing and working angle mechanism comprises a drive shaft, a cylindrical hollow camshaft fitted to an outer periphery of the drive shaft to be rotatable relatively about the drive shaft, a non-uniform velocity coupling including an annular disc disposed between the drive shaft and the camshaft for transmitting motion of rotation from the drive shaft to the camshaft, permitting a phase change of the camshaft relative to the drive shaft with non-uniform rotation during eccentric motion of the annular disc, and a control housing rotatably supporting the annular disc. Also provided is a decentering mechanism supporting the control housing rockably to produce the eccentric motion of the annular disc. A locus of eccentric motion of the center of the annular disc arranged in the left bank and a locus of eccentric motion of the center of the annular disc arranged in the right bank are essentially symmetrical with respect to the line perpendicular to a line segment between and including two central axes of said drive shafts of the two cylinder banks. A direction of eccentric motion of the center of the annular disc arranged in the right bank is opposite to a direction of eccentric motion of the center of the annular disc arranged in the left bank.

Valve-operating device for engine with two banks and variable valve

A device for moving a hollow cam relative to a driving shaft includes an intermediate member between a drive member fixed to the driving shaft and a driven member fixe to the hollow cam. A cam ring in the form of an eccentric cam is disposed between the driving shaft and the intermediate member to maintain eccentric rotation of the intermediate member relative to the driving shaft. A driver mechanism controls the angular position of the cam ring.

Device for moving cam relative to its driving shaft

A drive shaft is synchronously driven by an internal combustion engine. A cylindrical hollow cam shaft is rotatably disposed about the drive shaft. The cam shaft has thereon a cam which actuates a valve of the engine. A first flange is formed on one end of the cam shaft. A second flange is connected to the drive shaft to rotate therewith. The second flange faces the first flange. First and second radially extending grooves are formed in mutually facing surfaces of the first and second flanges respectively. The first and second grooves are arranged at opposite sides with respect to an axis of the drive shaft. An annular disc is disposed between the first and second flanges. The annular disc has first and second pins which are slidably engaged with the first and second grooves respectively. A control housing rotatably receives therein the annular disc. The control housing is pivotal in a direction perpendicular to an axis of the drive shaft and has therein a cam receiving circular opening. A control shaft has thereon a circular eccentric cam which is slidably received in the cam receiving circular opening of the control housing. A pair of annular flanges are provided on the control shaft to intimately put therebetween a thicker portion of the control housing thereby to suppress an undesired axial displacement of the control housing on and along the control shaft.

Variable valve timing and lift mechanism of internal combustion engine

A valve lifter and processing method therefor include a valve lifter surface to be installed in a recess of a cylinder head of an internal combustion engine. The method includes a grinding step for beveling, or tapering, the circumferential end of a cylindrical wall portion of the valve lifter which slidingly contacts the recess. Excess material resulting from the beveling process is then removed for smoothing the beveled circumferential end. The smoothed surface is then coated with a hardening layer for abrasion protection and smoother operational movement. As a final step, the hardening layer may be polished for further enhancement of operating performance.

Valve lifter surface and processing method thereof

According to a control strategy, a cylinder valve control device is monitored and operation of the engine is modified. The cylinder valve control device includes a driving shaft driven by the engine to drive an intermediate member which in turn drives a cam arranged to open an engine intake valve, and a driver which is operative in response to a command to vary an amount of eccentricity of the intermediate member with respect to a shaft axis of the driving shaft. During one mode of engine operation, the intermediate member is supported in a support for rotation about an axis in eccentric condition with respect to the shaft axis to accelerate and decelerate the cam with respect to rotation of the driving shaft. During another mode of engine operation, the intermediate member is in concentric condition with respect to the shaft axis to provide a synchronous motion of the cam with rotation of the driving shaft. In response to the eccentricity of the intermediate member, the engine operation is modified.

Engine cylinder valve control system

In an apparatus for detecting a valve lifting characteristic of a cam shaft assembly for use in a multi-cylinder internal combustion engine with a cylinder head to control opening and closure of cylinder valves, a sensor which is so arranged and constructed as to detect the valve lifting characteristic of the cam shaft assembly is disposed on an end of at least one of either a first eccentric control cam or a second eccentric control cam, both of the first and second eccentric cams being rotatably coupled with an intermediate member supported by a support so as to vary an eccentricity of the intermediate member to a shaft axis of a driven shaft according to a rotation position of the first eccentric control cam, the first and second eccentric control cam, the intermediate member, the support, and the driven shaft constituting the cam shaft assembly. In an embodiment, a potentiometer is attached onto an end of a control rod integrally formed with the first eccentric control cam, the other end of the control rod being attached with a hydraulic actuator to rotate the control rod according to an engine driving condition.

Apparatus for detecting valve lifting characteristic of cam shaft

An engine valve control mechanism is disclosed in which the eccentricity of an intermediate member can be varied by a pivotable support and a valve lift of a cylinder valve is varied in response to the varying eccentricity such that a reduced valve lift is produced during operation with the intermediate member held eccentric with a driving shaft which drives, via the intermediate member, a cam which actuates the valve.

Engine valve control mechanism

A cam shaft assembly comprises a first coupling between a drive collar rotatable with a driving shaft and an annular disc at a first position spaced from the shaft axis, and a second coupling between the disc and said hollow cam at a second position angularly spaced from said first position with respect to the shaft axis. The first and second couplings are so spaced from the shaft axis that they are at varying distances from the axis of the disc during operation. Each of the first and second couplings has a movable connection with the disc to permit the variation in its distance from the axis of the disc. The disc is rotatably supported in a disc housing. A control rod is mounted for rotation and has an eccentric control cam which controls movement of the disc housing. A pivot shaft extends through the disc housing for allowing movement of the disc housing following the eccentric control cam in which said plurality of hollow cams are disposed.

Growing community of inventors

Atsugi, Japan

Akira Hidaka